20668669 has 4 divisors (see below), whose sum is σ = 23621344. Its totient is φ = 17715996.

The previous prime is 20668667. The next prime is 20668693. The reversal of 20668669 is 96686602.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20668669 - 2¹ = 20668667 is a prime.

It is a super-2 number, since 2×20668669² = 854387756463122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20668667) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1476327 + ... + 1476340.

It is an arithmetic number, because the mean of its divisors is an integer number (5905336).

Almost surely, 2^20668669 is an apocalyptic number.

It is an amenable number.

20668669 is a deficient number, since it is larger than the sum of its proper divisors (2952675).

20668669 is an equidigital number, since it uses as much as digits as its factorization.

20668669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2952674.

The product of its (nonzero) digits is 186624, while the sum is 43.

The square root of 20668669 is about 4546.2807876329. The cubic root of 20668669 is about 274.4337394800.

The spelling of 20668669 in words is "twenty million, six hundred sixty-eight thousand, six hundred sixty-nine".